IPAC2011 - List of Authors (Rosenzweig, J.B.)

Paper

Title

Page

Bunch Length Diagnostic with Sub-femtosecond Resolution for High Brightness Electron Beams

1967

G. Andonian, E. Hemsing, P. Musumeci, J.B. Rosenzweig
UCLA, Los Angeles, California, USA
A.Y. Murokh
RadiaBeam, Santa Monica, USA
D. Xiang
SLAC, Menlo Park, California, USA

Next generation light sources require electron beams with high peak currents, typically achieved by compression techniques. The temporal diagnosis of these ultra-short beams demands enhanced resolution. We describe a scheme to achieve a temporal resolution on the order of sub-femtoseconds. The scheme is based on encoding the longitudinal profile of the beam on a transverse angular modulation, based on an interaction between the electron beam and a high-power laser in an undulator. This imposes a fast-sweep of the beam, on the order of sub-femtoseconds. A subsequent sweep in the orthogonal dimension by an rf deflecting cavity, imposes a "slow-sweep" on the order of sub-picoseconds. In this paper, we demonstrate applicability of this diagnostic scheme at the BNL ATF and specify the techniques required for practical applicability.

Slides WEOBB02 [1.120 MB]

WEPC137

Undulator Radiation Simulation by QUINDI

2316

D. Schiller, E. Hemsing, J.B. Rosenzweig
UCLA, Los Angeles, California, USA

QUINDI, a code developed to simulate coherent emission from bending systems, has been upgraded to include undulators as a beamline element. This approach allows us to better model the radiation produced by a relativistic electron bunch propagating through such a device.

WEPZ034

Double Resosnant Plasma Wakefields

2838

B.D. O'Shea, A. Fukasawa, B. Hidding, J.B. Rosenzweig, S. Tochitsky
UCLA, Los Angeles, California, USA
D.L. Bruhwiler
Tech-X, Boulder, Colorado, USA

Present work in Laser Plasma Accelerators focuses on a single laser pulse driving a non-linear wake in a plasma. Such single pulse regimes require ever increasing laser power in order to excite ever increasing wake amplitudes. Such high intensity pulses can be limited by instabilities as well engineering restrictions and experimental constraints on optics. Alternatively we present a look at resonantly driving plasmas using a laser pulse train. In particular we compare analytic, numerical and VORPAL simulation results to characterize a proposed experiment to measure the wake resonantly driven by four Gaussian laser pulses. The current progress depicts the interaction of 4 CO2 laser pulses, λlaser = 10.6μm, of 3 ps full width at half max- imum (FWHM) length separated peak-to-peak by 18 ps, each of normalized vector potential a0 ≃ 0.7. Results con- firm previous discourse (*,**) and show, for a given laser pro- file, an accelerating field on the order of 900 MV/m, for a plasma satisfying the resonant condition, ωp=π/t_fwhm.
* Umstadter, D., et al, Phys. Rev. Lett. 72, 1224
** Umstadter, D., et al, Phys. Rev. E 51, 3484

THPC101

Fitting Formulas for Space-charge Dominated Free-electron Lasers

3122

G. Marcus, E. Hemsing, J.B. Rosenzweig
UCLA, Los Angeles, California, USA

A simple power-fit formula for calculating the gain length of the fundamental Gaussian mode of a free-electron laser having strong space-charge effects in the 3D regime has been obtained. This tool allows for quick evaluation of the free-electron laser performance in the presence of diffraction, uncorrelated energy spread, and longitudinal space-charge effects. Here, we use it to evaluate the performance of high-gain FEL amplifiers considered candidates as high average power light sources. Results are compared with detailed numerical particle simulations using the free-electron laser code Genesis.

THPC102

Production of Coherent Optical \vCerenkov Radiation in Silica Aerogel

3125

F.H. O'Shea, J.B. Rosenzweig
UCLA, Los Angeles, California, USA

As a demonstration of the apposite properties of silica aerogel as an electron beam diagnostic we intend to use it to produce coherent optical Cˇ erenkov radation (COCR). In this paper we propose an experiment and provide details of the challenges to be overcome in producing COCR.

THPC100

Full Temporal Reconstruction using an Advanced Longitudinal Diagnostic at the SPARC FEL

3119

G. Marcus, J.B. Rosenzweig
UCLA, Los Angeles, California, USA
M. Artioli, F. Ciocci, L. Giannessi, A. Petralia, M. Quattromini, V. Surrenti
ENEA C.R. Frascati, Frascati (Roma), Italy
A. Bacci, M. Bellaveglia, E. Chiadroni, G. Di Pirro, M. Ferrario, G. Gatti, A. Mostacci, A.R. Rossi
INFN/LNF, Frascati (Roma), Italy
A. Cianchi
INFN-Roma II, Roma, Italy
V. Petrillo
Istituto Nazionale di Fisica Nucleare, Milano, Italy
J.V. Rau
ISM-CNR, Rome, Italy

The Production of ultra-short (sub 100 fs) single-spike radiation possessing full longitudinal coherence from a free-electron laser (FEL) has been the subject of intense study. A Frequency-Resolved Optical Gating (FROG) diagnostic has been developed and tested at UCLA, which has the capability of providing a longitudinal reconstruction of these ultra-fast pulses. This paper reports the results of the application of the diagnostic at the SPARC FEL facility.

Paper	Title	Page
WEOBB02	Bunch Length Diagnostic with Sub-femtosecond Resolution for High Brightness Electron Beams	1967
	G. Andonian, E. Hemsing, P. Musumeci, J.B. Rosenzweig UCLA, Los Angeles, California, USA A.Y. Murokh RadiaBeam, Santa Monica, USA D. Xiang SLAC, Menlo Park, California, USA
	Next generation light sources require electron beams with high peak currents, typically achieved by compression techniques. The temporal diagnosis of these ultra-short beams demands enhanced resolution. We describe a scheme to achieve a temporal resolution on the order of sub-femtoseconds. The scheme is based on encoding the longitudinal profile of the beam on a transverse angular modulation, based on an interaction between the electron beam and a high-power laser in an undulator. This imposes a fast-sweep of the beam, on the order of sub-femtoseconds. A subsequent sweep in the orthogonal dimension by an rf deflecting cavity, imposes a "slow-sweep" on the order of sub-picoseconds. In this paper, we demonstrate applicability of this diagnostic scheme at the BNL ATF and specify the techniques required for practical applicability.
	Slides WEOBB02 [1.120 MB]

WEPC137	Undulator Radiation Simulation by QUINDI	2316
	D. Schiller, E. Hemsing, J.B. Rosenzweig UCLA, Los Angeles, California, USA
	QUINDI, a code developed to simulate coherent emission from bending systems, has been upgraded to include undulators as a beamline element. This approach allows us to better model the radiation produced by a relativistic electron bunch propagating through such a device.

WEPZ034	Double Resosnant Plasma Wakefields	2838
	B.D. O'Shea, A. Fukasawa, B. Hidding, J.B. Rosenzweig, S. Tochitsky UCLA, Los Angeles, California, USA D.L. Bruhwiler Tech-X, Boulder, Colorado, USA
	Present work in Laser Plasma Accelerators focuses on a single laser pulse driving a non-linear wake in a plasma. Such single pulse regimes require ever increasing laser power in order to excite ever increasing wake amplitudes. Such high intensity pulses can be limited by instabilities as well engineering restrictions and experimental constraints on optics. Alternatively we present a look at resonantly driving plasmas using a laser pulse train. In particular we compare analytic, numerical and VORPAL simulation results to characterize a proposed experiment to measure the wake resonantly driven by four Gaussian laser pulses. The current progress depicts the interaction of 4 CO2 laser pulses, λlaser = 10.6μm, of 3 ps full width at half max- imum (FWHM) length separated peak-to-peak by 18 ps, each of normalized vector potential a0 ≃ 0.7. Results con- firm previous discourse (,) and show, for a given laser pro- file, an accelerating field on the order of 900 MV/m, for a plasma satisfying the resonant condition, ωp=π/t_fwhm. Umstadter, D., et al, Phys. Rev. Lett. 72, 1224 ** Umstadter, D., et al, Phys. Rev. E 51, 3484

THPC101	Fitting Formulas for Space-charge Dominated Free-electron Lasers	3122
	G. Marcus, E. Hemsing, J.B. Rosenzweig UCLA, Los Angeles, California, USA
	A simple power-fit formula for calculating the gain length of the fundamental Gaussian mode of a free-electron laser having strong space-charge effects in the 3D regime has been obtained. This tool allows for quick evaluation of the free-electron laser performance in the presence of diffraction, uncorrelated energy spread, and longitudinal space-charge effects. Here, we use it to evaluate the performance of high-gain FEL amplifiers considered candidates as high average power light sources. Results are compared with detailed numerical particle simulations using the free-electron laser code Genesis.

THPC102	Production of Coherent Optical \vCerenkov Radiation in Silica Aerogel	3125
	F.H. O'Shea, J.B. Rosenzweig UCLA, Los Angeles, California, USA
	As a demonstration of the apposite properties of silica aerogel as an electron beam diagnostic we intend to use it to produce coherent optical Cˇ erenkov radation (COCR). In this paper we propose an experiment and provide details of the challenges to be overcome in producing COCR.

THPC100	Full Temporal Reconstruction using an Advanced Longitudinal Diagnostic at the SPARC FEL	3119
	G. Marcus, J.B. Rosenzweig UCLA, Los Angeles, California, USA M. Artioli, F. Ciocci, L. Giannessi, A. Petralia, M. Quattromini, V. Surrenti ENEA C.R. Frascati, Frascati (Roma), Italy A. Bacci, M. Bellaveglia, E. Chiadroni, G. Di Pirro, M. Ferrario, G. Gatti, A. Mostacci, A.R. Rossi INFN/LNF, Frascati (Roma), Italy A. Cianchi INFN-Roma II, Roma, Italy V. Petrillo Istituto Nazionale di Fisica Nucleare, Milano, Italy J.V. Rau ISM-CNR, Rome, Italy
	The Production of ultra-short (sub 100 fs) single-spike radiation possessing full longitudinal coherence from a free-electron laser (FEL) has been the subject of intense study. A Frequency-Resolved Optical Gating (FROG) diagnostic has been developed and tested at UCLA, which has the capability of providing a longitudinal reconstruction of these ultra-fast pulses. This paper reports the results of the application of the diagnostic at the SPARC FEL facility.